Add support for Want-Digest on LDP-RSs

acoburn · acoburn · commit 66e58a751313 · 2017-04-10T20:25:43.000-04:00
Resolves #33
diff --git a/src/Controller/ResourceController.php b/src/Controller/ResourceController.php
@@ -13,15 +13,6 @@
 
 class ResourceController implements ControllerProviderInterface
 {
-    const LDP_NS = "http://www.w3.org/ns/ldp#";
-    const RDF_NS = "http://www.w3.org/1999/02/22-rdf-syntax-ns#";
-    const DCTERMS_NS = "http://purl.org/dc/terms/";
-
-    // Its a class, no need to pass all via arguments around.
-    private $modifiedTime = null;
-    private $contentLength = 0;
-    private $eTag = null;
-
     /**
      * {@inheritdoc}
      */
@@ -59,12 +50,13 @@ public function get(Application $app, Request $request, $path)
             return new Response("Not Found", 404);
         }
 
-        //$responseFormat = $this->getResponseFormat($app['config']['validRdfFormats'], $request);
-        //$responseMimeType = $this->getResponseMimeType($app['config']['validRdfFormats'], $request);
         $formats = $app['config']['validRdfFormats'];
+        $options = [
+            "contentDisposition" => $app['config']['contentDisposition']
+        ];
 
         $resource = ResourceFactory::create($requestedPath, $formats);
-        return $resource->respond($app, $request);
+        return $resource->respond($app, $request, $options);
     }
 
     /**
diff --git a/src/Model/BasicContainer.php b/src/Model/BasicContainer.php
@@ -6,6 +6,9 @@
 use Symfony\Component\HttpFoundation\Request;
 use Symfony\Component\HttpFoundation\Response;
 
+/**
+ * A class representing an LDP BasicContainer
+ */
 class BasicContainer extends Resource
 {
     /**
@@ -25,11 +28,13 @@ public function respond(Application $app, Request $request, array $options = arr
         ];
 
         $res = new Response();
+        $res->setPublic();
         $res->headers->add($headers);
         $res->setLastModified($modifiedTime);
         $res->setEtag($this->getEtag($responseFormat, $request->headers->get('range')));
 
         if (!$res->isNotModified($request)) {
+            $algorithm = $this->getDigestAlgorithm($request->headers->get('want-digest'));
             $subject = $request->getUri();
             $predicate = self::LDP_NS . "contains";
 
@@ -73,11 +78,22 @@ public function respond(Application $app, Request $request, array $options = arr
                 $data = json_decode($graph->serialise("jsonld"), true);
                 $dataset = $this->mapJsonLdForHTML($data, $app['config']['prefixes']);
                 $template = $app['config']['template'];
-                return $app['twig']->render($template, ["id" => $subject, "dataset" => $dataset]);
+                $content = $app['twig']->render($template, ["id" => $subject, "dataset" => $dataset]);
             } else {
                 $content = $graph->serialise($responseFormat);
             }
 
+            if ($request->headers->get('range') === null) {
+                switch ($algorithm) {
+                    case "md5":
+                        $res->headers->set('Digest', 'md5=' . $this->md5($content));
+                        break;
+                    case "sha1":
+                        $res->headers->set('Digest', 'sha1=' . $this->sha1($content));
+                        break;
+                }
+            }
+
             $res->setContent($content);
         }
 
diff --git a/src/Model/NonRDFSource.php b/src/Model/NonRDFSource.php
@@ -6,6 +6,9 @@
 use Symfony\Component\HttpFoundation\Request;
 use Symfony\Component\HttpFoundation\Response;
 
+/**
+ * A class representing an LDP NonRDFSource
+ */
 class NonRDFSource extends Resource
 {
     /**
@@ -18,13 +21,19 @@ public function respond(Application $app, Request $request, array $options = arr
             $contentDisposition = $options['contentDisposition'];
         }
         $res = new Response();
+        $res->setPublic();
         $res->headers->add($this->getHeaders($contentDisposition));
         $res->setLastModified(\DateTime::createFromFormat('U', filemtime($this->path)));
         $res->setEtag($this->getEtag($request->headers->get('range')));
         if (!$res->isNotModified($request)) {
-            $digest = $this->wantDigest($request->headers->get('want-digest'));
-            if ($digest) {
-                $res->headers->set('Digest', $digest);
+            $algorithm = $this->getDigestAlgorithm($request->headers->get('want-digest'));
+            switch ($algorithm) {
+                case "md5":
+                    $res->headers->set('Digest', "md5=" . $this->md5());
+                    break;
+                case "sha1":
+                    $res->headers->set('Digest', "sha1=" . $this->sha1());
+                    break;
             }
             foreach ($this->formats as $type) {
                 $description = $this->path . "." . $type['extension'];
diff --git a/src/Model/RDFSource.php b/src/Model/RDFSource.php
@@ -6,6 +6,9 @@
 use Symfony\Component\HttpFoundation\Request;
 use Symfony\Component\HttpFoundation\Response;
 
+/**
+ * A class representing an LDP RDFSource
+ */
 class RDFSource extends Resource
 {
     /**
@@ -17,6 +20,7 @@ public function respond(Application $app, Request $request, array $options = arr
         $responseFormat = $this->getResponseFormat($request);
 
         $res = new Response();
+        $res->setPublic();
         $res->headers->add($this->getHeaders($responseMimeType));
         $res->setLastModified(\DateTime::createFromFormat('U', filemtime($this->path)));
         $res->setEtag($this->getEtag($responseFormat, $request->headers->get('range')));
@@ -32,10 +36,17 @@ public function respond(Application $app, Request $request, array $options = arr
                 }
             }
 
+            $algorithm = $this->getDigestAlgorithm($request->headers->get('want-digest'));
             if ($this->canStream($responseFormat)) {
-                $digest = $this->wantDigest($request->headers->get('want-digest'));
-                if ($digest) {
-                    $res->headers->set('Digest', $digest);
+                if ($request->headers->get('range') === null) {
+                    switch ($algorithm) {
+                        case "md5":
+                            $res->headers->set('Digest', 'md5=' . $this->md5());
+                            break;
+                        case "sha1":
+                            $res->headers->set('Digest', 'sha1=' . $this->sha1());
+                            break;
+                    }
                 }
                 $filename = $this->path;
                 $stream = function () use ($filename) {
@@ -49,10 +60,21 @@ public function respond(Application $app, Request $request, array $options = arr
                     $data = json_decode($graph->serialise("jsonld"), true);
                     $dataset = $this->mapJsonLdForHTML($data, $app['config']['prefixes']);
                     $template = $app['config']['template'];
-                    return $app['twig']->render($template, ["id" => $request->getURI(), "dataset" => $dataset]);
+                    $content = $app['twig']->render($template, ["id" => $request->getURI(), "dataset" => $dataset]);
                 } else {
-                    $res->setContent($graph->serialise($responseFormat));
+                    $content = $graph->serialise($responseFormat);
                 }
+                if ($request->headers->get('range') === null) {
+                    switch ($algorithm) {
+                        case "md5":
+                            $res->headers->set('Digest', 'md5=' . $this->md5($content));
+                            break;
+                        case "sha1":
+                            $res->headers->set('Digest', 'sha1=' . $this->sha1($content));
+                            break;
+                    }
+                }
+                $res->setContent($content);
             }
         }
         return $res;
diff --git a/src/Model/Resource.php b/src/Model/Resource.php
@@ -5,6 +5,9 @@
 use Silex\Application;
 use Symfony\Component\HttpFoundation\Request;
 
+/**
+ * A class representing an LDP Resource
+ */
 abstract class Resource
 {
     const LDP_NS = "http://www.w3.org/ns/ldp#";
@@ -42,60 +45,59 @@ abstract public function respond(Application $app, Request $request, array $opti
      * @return string
      *    The SHA1 checksum of the file
      */
-    public function sha1()
+    public function sha1($content = null)
     {
-        if (is_file($this->path)) {
+        if ($content !== null) {
+            return sha1($content);
+        } elseif (is_file($this->path)) {
             return sha1_file($this->path);
         }
         return null;
     }
 
     /**
-     * Apply a want-digest header, if applicable
+     * Compute the MD5 checksum of a file
+     * @return string
+     *    The MD5 checksum of the file
+     */
+    public function md5($content = null)
+    {
+        if ($content !== null) {
+            return md5($content);
+        } elseif (is_file($this->path)) {
+            return md5_file($this->path);
+        }
+        return null;
+    }
+
+    /**
+     * Given a want-digest header, return the applicable algorithm
      *
      * @param $wantDigestHeader
      *      The Want-Digest header
      * @return string
-     *      The instance digest, if relevant
+     *      The algorithm name, if any
      */
-    protected function wantDigest($wantDigestHeader)
+    protected function getDigestAlgorithm($wantDigestHeader)
     {
+        $validAlgorithms = ["md5", "sha1"];
+        $bestAlgorithm = null;
         if ($wantDigestHeader) {
             $maxQVal = 0.0;
-            $bestAlgorithm = null;
             foreach (explode(",", $wantDigestHeader) as $algorithm) {
                 $parts = explode(";", $algorithm);
                 $qVal = 1.0;
                 if (count($parts) > 1 && strpos($parts[1], "q=") === 0) {
                     $qVal = floatval(trim(substr($parts[1], 2)));
                 }
                 $alg = strtolower(trim($parts[0]));
-                if ($qVal > $maxQVal && in_array($alg, ["md5", "sha1"])) {
+                if ($qVal > $maxQVal && in_array($alg, $validAlgorithms)) {
                     $bestAlgorithm = $alg;
                     $maxQVal = $qVal;
                 }
             }
-            switch($bestAlgorithm) {
-                case "md5":
-                    return "md5=" . $this->md5();
-                case "sha1":
-                    return "sha1=" . $this->sha1();
-            }
         }
-        return null;
-    }
-
-    /**
-     * Compute the MD5 checksum of a file
-     * @return string
-     *    The MD5 checksum of the file
-     */
-    public function md5()
-    {
-        if (is_file($this->path)) {
-            return md5_file($this->path);
-        }
-        return null;
+        return $bestAlgorithm;
     }
 
     /**
diff --git a/src/TrellisConfiguration.php b/src/TrellisConfiguration.php
@@ -27,6 +27,9 @@ public function getConfigTreeBuilder()
                 ->booleanNode('debug')
                     ->defaultFalse()
                 ->end()
+                ->booleanNode('contentDisposition')
+                    ->defaultFalse()
+                ->end()
                 ->arrayNode('validRdfFormats')
                     ->prototype("array")
                         ->children()
diff --git a/test/Model/RDFSourceTest.php b/test/Model/RDFSourceTest.php
@@ -42,6 +42,7 @@ public function testGetRDFSource()
         $this->client->request('GET', "/nobel_914.ttl", [], [], ['HTTP_ACCEPT' => $request_mime]);
         $this->assertEquals(200, $this->client->getResponse()->getStatusCode(), "GET should be allowed.");
         $response = $this->client->getResponse();
+        $response->sendContent();
         $charset = $response->getCharset();
         $expected_mime = "{$request_mime}; charset={$charset}";
 
